Postfix stable release 2.8.5, 2.7.6, 2.6.12, 2.5.15

Postfix stable release 2.8.5, 2.7.6, 2.6.12, and 2.5.15 are
available. These contain fixes and workarounds for the Postfix
Milter client that were already included with the Postfix 2.9
experimental release.